1. Technical Field
The present invention relates to computer systems such as office computers, personal computers, and data processors including a wire/wireless keyboard, and more particularly, relates to a wire/wireless keyboard for use in a computer system and a method of operating the same.
2. Related Art
A typical computer system comprises a display unit, input devices such as a keyboard, a central processing unit (CPU) and data storage devices (e.g., floppy or hard disk drive) in a separate enclosure. This architecture is commonly used in "desk-top" personal computer systems, work stations, terminals and the like. The display unit, the keyboard and the main body containing all the essential circuitry of the computer may be integrated in a single, deployable portable housing structure, typically referred to as "lap-top" computers. Keyboard is typically connected to the main body through a connector cable to control operation of the computer. The cable which connects the keyboard to the main body of the computer is very stable and reliable for data transmission. However, the cable can be cumbersome, unattractive, and more importantly, cannot be moved freely because its length is standardized. If the connector cable is lengthened more than the standardized length, noise is often generated during data transmission.
Advanced wireless keyboard has been developed to provide a viable substitute for traditional keyboard for data transmission between the keyboard and the central processing unit of the computer without using cable. Examples of wireless keyboards can be found, for example, in U.S. Pat. No. 4,775,928 for Hand-Held Wireless Computer Controller System issued to Kendall et al., U.S. Pat. No. 5,081,628 for Cordless Keyboard issued to Maekawa et al., U.S. Pat. No. 5,247,285 for Standup Portable Personal Computer With Detachable Wireless Keyboard And Adjustable Display issued to Yokota et al., U.S. Pat. No. 5,644,338 for Ergonomic Laptop Computer And Ergonomic Keyboard issued to Bowen, and U.S. Pat. No. 5,615,393 for Computer System Having A Cordless Keyboard And An Induction Coil In A Plug-In Electronic Card Module issued to Kikinis et al.
Wireless keyboard transmits data to the central processing unit (CPU) of the computer via either radio frequency (RF) signals or infrared (IR) signals. While contemporary designs of wireless keyboards are becoming acceptable substitutes for cable keyboards, I have observed that there are still problems associated with wireless transmission. The first problem is noise that may be generated during wire communication because of other wireless devices in the proximity of the computer system. The second problem is limited use of battery power for the wireless keyboard. The wireless keyboard must be designed to operate for extended period of time.